zorro: Make zorro_bus_type const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the zorro_bus_type variable to be a constant
structure as well, placing it into read-only memory which can not be
modified at runtime.

Suggested-by: Greg Kroah-Hartman <[e-mail]>
Signed-off-by: Ricardo B. Marliere <[e-mail]>
Reviewed-by: Geert Uytterhoeven <[e-mail]>
Reviewed-by: Greg Kroah-Hartman <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Geert Uytterhoeven <[e-mail]>

drivers/zorro/zorro-driver.c

···
 	return 0;
 }
 
-struct bus_type zorro_bus_type = {
+const struct bus_type zorro_bus_type = {
 	.name		= "zorro",
 	.dev_name	= "zorro",
 	.dev_groups	= zorro_device_attribute_groups,

drivers/zorro/zorro.h

···
      *  Zorro bus
      */
 
-extern struct bus_type zorro_bus_type;
+extern const struct bus_type zorro_bus_type;
 
 
 #ifdef CONFIG_ZORRO_NAMES